Sorbent-based regenerative hemodialysis systems can provide benefits such as the ability to provide hemodialysis treatments with a reduced volume of source water and without the requirement to receive the source water from water purification systems that are commonly used to filter and purify the dialysate for hemodialysis treatments. Some sorbent-based regenerative hemodialysis systems can provide a hemodialysis treatment using a smaller quantity of potable water than traditional single-pass hemodialysis systems. Purified water can be difficult to obtain in many locations through-out the world. Eliminating the need to provide fresh purified water for each dialysis session can enable patients in such areas to obtain necessary treatment.
Microbiologically ultrapure dialysate is desirable for hemodialysis treatment. Ultrapure dialysate is defined as dialysate having less than 0.1 colony forming units per milliliter and less than 0.03 endotoxin units per milliliter. Microbial filters, such as ultra-filters, can be used to remove microorganisms and other unwanted substances such as endotoxins from water used to prepare dialysate, or from the dialysate itself, before the dialysate enters the dialyzer in order to prevent their transfer to the patient during hemodialysis. To minimize the cost of providing hemodialysis treatment, using non-disposable dialysate flow path components, and multi-use ultra-filters that can be used for more than a single treatment session is often desirable. Non-disposable dialysate flow paths must also be routinely cleaned and disinfected to prevent microbial growth and formation of bio-film so that viable microorganisms and remnants of dead microorganisms, such as endotoxins, are minimized.
Sorbent-based regenerative hemodialysis systems can purify potable water to produce dialysate for hemodialysis treatment. In addition to chemical purification, sorbents can be designed to remove microbiological and particulate contaminants that may also exist in potable water. An ultra-filter can be added to the dialysate preparation flow path between the sorbent outlet and the dialyzer inlet to remove remaining microorganisms and endotoxin from the dialysate to ensure that a microbiologically ultrapure dialysate is produced. To achieve a long, economically efficient ultra-filter service life, removal of particulate matter that could clog the fine pores of an ultra-filter from the liquid by the sorbent before the liquid passes through the ultra-filter is important.
The sorbents may be removed from the dialysate flow path of sorbent-based regenerative hemodialysis system during rinsing, cleaning and disinfection of the dialysate flow path. However, if the sorbents are not present in the flow path to remove chemical contaminants, microorganisms, and fine particulate matter contained in the incoming source water, then the dialysate flow path may be contaminated and may require alternate cleaning processes. Further, the fine pores of the ultra-filter may become clogged, rendering the ultra-filter unusable after only a brief service life.
Hence, there is a need for a system whereby purified water can be generated and stored within the dialysis system for later cleaning and disinfection, thereby eliminating the need for attaching an external source of purified water after each dialysis session. There is also a need for a system allowing for a single-time connection of the rinse water reservoir to the rest of the dialysis system, thus simplifying the cleaning and disinfection process.